The present invention generally relates to valves, and more particularly to a replaceable valve seat ring for fluid flow valves.
Fluid valves are used in a wide range of fluid process and control system applications for controlling various flow parameters of a process fluid. A wide variety of valve types are known and can include, for example, dump valves, control valves, throttling valves, and the like. Similarly, fluid process and control systems are utilized for handling a myriad of different fluid media.
A typical valve has a fluid inlet coupled through a flow control or orifice region to a fluid outlet. A closure device of some kind is typically provided in the flow control region with a portion that is movable to control fluid flow from the valve inlet to the valve outlet. The movable portion is often a valve plug that can be moved to bear against a corresponding fixed seating surface of the closure device to selectively shut off flow of fluid through the valve. During continued use of such a valve, the seating surface of the closure device inevitably becomes worn or damaged. Inadequate flow shut off of the closure device will result, causing poor performance or failure of the valve. Thus, the valve seating surface must eventually be repaired or replaced, or the entire valve must be replaced to again achieve proper function of the valve.
In one known example, a valve seat ring has a seating surface and is disposed within a flow control or orifice region of the valve. The seat ring is removable in order to replace the seat ring or to repair the seating surface. This type of removable seat ring has a hex-shaped head extending upward from a top surface of the ring. The hex head is adapted to accept a particular standard size hex socket or wrench for installing or removing the ring. However, the upwardly protruding hex head negatively interferes with fluid flow through the orifice region of the valve, and the technician must have the particular tool size on hand.
In another known example, a pair of small blind bores formed into the top surface of the seat ring. These bores are adapted to receive two spaced apart prongs of a specialized tool to install or remove the ring. The technician must have access to this specialized tool at all times in order to service this type of valve.